There have been described, in EP-139,481, cosmetic compositions using, as agents for modifying the surface of inorganic compounds, for the purpose of increasing the dispersibility thereof, either an N-monoacylated derivative of a basic amino acid in which the aliphatic acyl group has from 8 to 22 carbon atoms or an N,N-diacylated derivative of a basic amino acid in which the aliphatic acyl groups, which are identical or different, having from 1 to 22 carbon atoms.
There have also been described, in EP-336,265, cosmetic compositions for hair shaping comprising, as surface-active agents, an N-monoacylated derivative of a basic amino acid in which the aliphatic acyl group has from 8 to 22 carbon atoms.
The acylated derivatives of the basic amino acids described previously are, however, very difficult and even impossible to compact.
Now, it is known that certain cosmetic, pharmaceutical and hygiene compositions are presented in the so-called "compact" form. They are anhydrous compositions consisting mainly of solid particles and of a fatty binder (oils or mixture of oils and waxes) and are shaped by compression or by pouring into a container which acts as mold.
The development of such compositions raises, however, many difficulties because the final product must be sufficiently homogeneous and compact to have a good ability to be removed and, moreover, to avoid fragmentation which may be caused, especially, by impacts.